Not quite sure which Diono car seat to buy?

I get it, with so many models that sound and look the same it can be tough to find a comprehensive (and independent) Diono car seat comparison.

The good news is we have you covered! In this guide, you’ll discover the best Diono car seat so you can rest assured you’re making a good choice for your child.

But first, a bit about the Diono car seat brand.

The company is proud to offer more than 20 years of American engineering experience to the car seat industry. They focus on innovative problem solving and providing groundbreaking solutions for safety.

Above all, Diono’s car seats are built for safety with reinforced steel core frames. They feature Safe+ side impact protection with 8 interlocking layers of steel, plastic, and foam for ultimate protection. Here are other key takeaways we had after testing the various Diono car seats.

What We Like
They’re slim seats, you can likely fit three across one row
Above average padding, very comfortable memory foam
A higher and narrow design is great for taller kids
Lightweight for easy portability
What We Dislike
Can be a bit awkward in rear facing positions

After comparing all of Diono’s car seats, which includes Radian Series (3R, 3RX, 3RXT, 3QX, 3QXT) , Diono Monterey, and Diono Evernett, we concluded that the Radian 3QXT is the best Diono car seat to buy. 


5 Best Diono Car Seats [2023 Lightest & Most Affordable] 15 Best Diono Car Seats [2023 Lightest & Most Affordable] 2

The flagship seat in the Diono lineup
Impressive rear facing weight limit
High quality steel core and frame, we love the anti-rebound bar
More affordable than the 3QXT, but missing a few features
Conveniently foldable for storage
Expensive, so you might as well spend a small amount more for the 3QXT

5 Best Diono Car Seats [2023 Lightest & Most Affordable] 55 Best Diono Car Seats [2023 Lightest & Most Affordable] 6

The original seat that made Diono popular
The most affordable convertible option
Easily fits three across in many cars
Comes in some great color options
Great for long car rides, kept our child cool and relaxed
Easy to install LATCH system

5 Best Diono Car Seats [2023 Lightest & Most Affordable] 95 Best Diono Car Seats [2023 Lightest & Most Affordable] 10

Very lightweight
Most portable option in our lineup
High quality memory foam for a comfortable ride


Diono Car Seats Reviews

Continue reading for a breakdown of the company’s top 5 convertible car seats so that you can make an informed decision about the best choice for your family.

Height and Weight Specifications

3R3RX3QX3QXTMonterey 4DXT Everett NXT
Rear-facing5 – 50 lb5 – 50 lb4 – 50 lb 4 – 50 lb
Forward Facing22 – 65 lb22 – 65 lb22 – 65 lb
Booster Mode40 – 120 lb40 – 120 lb40 – 120 lb40 – 120 lb40-120 lbs.40-120 lbs.

Pick #1: Diono Radian 3QXT Rear & Forward Facing – Best Overall

What We Like
Supports rear-facing until 50 pounds, longer than most
Steel core and frame
Anti-rebound bar
Easy click installation 
Can wash and dry covers
What We Dislike
While fitting three across is possible, installation can be challenging
Expensive option

I chose the Diono Radian 3QXT as the best overall Diono car seat because not only is it convertible until the child is 120-pounds, but it has a long 10-year usage and is perfect as an infant seat.

It has a ton of fantastic features that justifies the price tag such as the 8 layers of side impact protection and slim profile. 

This was by far my favorite Diono car seat. As soon as I removed it from the packaging I knew it was going to be a great fit. First, it was installed in a snap. The easy click installation made the process simple and without frustration. The slim profile allowed me to install this seat plus two others in the back seat of my midsize car. 

There is a 4-stage newborn protection package that impressed me. Additionally, the 12-position headrest allowed me to adjust it to fit my child’s unique needs.

My child ended up having an accident in the seat, but I took the fabric off and put it in the washing machine. This is a huge deciding factor for me when I look for a practical car seat.  

This seat includes a four-stage newborn protection package: a newborn head and neck insert, a travel wedge to properly angle your baby to open airways, harness pads, and a positioning liner.

The 12-position headrest allows you to get full use out of this car seat, from rear-facing 4-50 pounds, forward-facing 22-65, and as a highback booster from 40-120. This seat isn’t cheap, but it will last your child 10 years, and keep them incredibly safe and protected.

The 17” slim profile fits three seats across the backseat, and it folds flat for travel. Diono uses Safe+ engineering, which means that their seats are rigorously tested for safety and feature a steel core and side-impact management pod.

The side-impact pod is on the side of the car seat that faces the door, and it’s designed to reroute the crash energy to the back of the car seat.

Pick #2: Diono Radian 3QX 4-In-1 – The “Grow With Your Child” Value Option

What We Like
Comfortable and padded
Extra rear-facing protection
Folds flat for travel
Anti-rebound bar
Can fit three-across
What We Dislike
Time-consuming installation
Heavy (it has a steel frame)

So my first thoughts about this car seat was that it was very strange looking. It’s a little clunky and weird like the 3QXT, but who cares, it’s ultra safe and comfortable.

It can be used for 10-years and accommodate kids up to 120-pounds. It’s less expensive than the 3QXT, but many of their features are similar such as the 6 layers of side-impact protection. 

Diono Radian

It was disappointing that it didn’t come with the newborn insert, but there’s a travel wedge, harness pads, and positioning liner. One of my favorite features of this car seat is that even though it seems bulky, it actually folds up flat for traveling and it can fit three across. The other issue I had with it was that installation was quite time-consuming.

So what are the differences between the 3QXT and the 3QX? To be honest, if you weren’t looking for them, you probably wouldn’t even notice.

The 3QX has six layers of side-impact protection instead of eight and does not have a side impact management pod (described in the review above).

It also doesn’t come with the newborn insert, although it does have the travel wedge, positioning liner, and harness pads. Virtually every other feature is the same, and you save some money.

If you ask us, this is an exceptionally safe all-in-one car seat that has many of the innovative above-and-beyond features that Diono prides itself on, including the anti-rebound bar.

Pick #3: Diono Radian 3R All-In-One Convertible – Most Affordable

What We Like
Very compact
Slim, you can easily fit 3 seats in a single row
Converts to a booster
Easily foldable for convenient storage options
What We Dislike
Straps are difficult to work with
Fewer safety features than the higher end Diono models

This car seat is Diono’s original “3 across” car seat. This means that these seats are so compact, they can be lined up comfortably next to each other in the back seat. This is great for parents with multiple car seat bound kids.

It offers optimal security for extended rear-facing and into front-facing too. The car seat’s frame is made of powerfully integrated steel and the seat itself is made of memory foam.

The walls are made of aluminum and are lined with energy-absorbing foam. The Radian 3R is super practical because it grows with your child from infancy up until childhood.  The seats rear-facing capabilities max out at 40 pounds, forward-facing at 65 pounds in the 5-point harness, and booster seat up to 100 pounds.

It’s also super convenient because it’s easy to install. It uses their own SuperLatch audible-click and visual-locking indicator, 5 shoulder and 3 buckle positions, an expandable footrest, and a non-slip rubber base.

Pick #4: Diono Monterey 4DXT With Expandable Height – Heavy-Duty Booster  

What We Like
Adjustable height and width
Easy and safe installation
Bright color options
Sturdy and comfortable (includes armrests and cup holders)
What We Disliked
Line dry recommended for seat cover (it IS machine-washable)
See above. Who has time for that!

If you’re looking for an expandable booster, then I suggest the Diono Monterey. It’s not cheap, but it’s a Diono, so it’s going to have that high price.

It does have breathable side panels that kept my child comfortable and cool while on a long car ride. Even though this booster doesn’t seem like much, it’s actually very durable. 

I loved how the cup holders were tucked away until they were needed. This allowed for more space on each side of the seat. Additionally, installation was a breeze with the LATCH connectors and I was able to adjust the height and width of the car seat.

I loved being able to adjust the width. This was something I’ve rarely seen on a car seat. One issue I came across was that you CAN machine wash it, but it has to be line dried.

Not only does it look cool enough that your ten-year-old won’t complain about it, but it also converts to a backless booster and comes in seven fun colors (including plum and bright yellow).

Our favorite features are the breathable side panels, wide and contoured seat, two cup holders that can be pulled out, and LATCH connectors for a safe and quick installation.

The best thing about this booster seat is that it’s incredibly heavy-duty, safe, and comfortable enough to sleep in. Booster seats tend to feel a bit flimsy and disposable, but that’s not the case with the Monterey 4DXT.

Pick #5: Diono Everett NXT Booster – Very Lightweight    

What We Like
Almost unbelievably light!
Portable, for easy swapping between vehicles
Ergonomic memory foam fabric to keep your child uber comfy
What We Dislike
We noticed a slight rattling noise while driving that was a bit annoying

This booster seat was one of the lightest I’ve come across. The first thing I noticed was the headrest. It looked like there was plenty of padding on each side to protect my little one in the event of an accident.

It can be used in 7 different positions and there’s a handle on the back of the seat that will adjust it. 

There are multiple ways the booster can be installed and they’re all fairly simple to understand. Additionally, if you have a messy child like I do, then you’ll appreciate the machine washable fabric as much as I did.

The only thing I noticed was a faint rattle from the car seat while I was driving, but that’s my only complaint. 

The headrest has seven different positions and can be easily altered by the handle on the back of the seat. It’s an ergonomic seat, which is really nice for providing impact protection and optimal comfort.

There are a few different ways this seat can be installed, but they are all relatively easy to understand and won’t cause a ton of frustration when trying to transport it between cars.

Its machine washable fabric and lightweight design make this booster seat a super convenient option for parents. Most other Diono car seats and boosters are much bulkier and heavier and that can make swapping vehicles a major hassle. Diono Everett is still considered a new car seat on the market, so there isn’t a ton of feedback on it yet.

Buyer’s Guide

When it comes to car seats, you’re going to want only the best for your child. In order to ensure you’re finding the perfect one, there are some things like safety and durability to keep in mind among other things.

Safety Features

A car seat’s safety rating should be your number one concern while shopping. All car seats are required to pass a 30 mph crash test to be released to the market (source).  Most car seat manufacturers have added safety features to increase a seat’s safety level as well.

Diono, in particular, uses high-quality steel in their car seat frames as well as comfortable padding to keep your baby safe and comfortable at the same time.


You’re also going to want a car seat that is durable and long-lasting. You’ll want to avoid a seat that seems to buckle under your child’s weight or has parts that break off easily. This ties back into the car seat’s safety features and their rating. If your car seat isn’t durable, it surely won’t keep your child safe in the event of a car accident.

Ease of Use

As important as a car seat’s safety features are, it won’t be any use if you’re too frustrated to constantly get your child in and out of the seat. This will only cause frustration from both you and your child.

This is especially important if you need to switch the seat between cars often. Find a car seat that boasts easy buckling and unbuckling and make sure to note how easy or difficult it is to install.


Above all, your child will need a comfortable car seat. When shopping around, take note of what comfort features a seat provides. Do they have an additional insert for the head? What about back and butt support? Nobody wants to deal with an annoyed and crying child in the car, so comfort is key. 

Are Diono Car Seats Worth It?

Overall, we feel that if you have older kids and you are going on long trips, the Diono car seats are great option. However, if you are still in the rear facing, I would opt for the Britax car seats. I say this because Diono car seats are tall and it is not ideal to use them in rear facing mode. 

Diono car seats provide safety and comfort. They have removable and machine washable covers for busy parents so keeping them clean is easy. These car seats are also easy to install and they are designed to fit 3 car seats across a medium-sized sedan.

The Safe+ headrests easily adjust to 12 positions to fit each child perfectly. Some rear-facing models include a steel anti-rebound bar which reduces rotation in the event of a collision. The anti-rebound bar also allows for more legroom in rear-facing seats, so children may remain rear-facing up to 50 pounds in some models.

Each seat has layers of carefully designed foam for comfort and safety. Diono car seats are rated to be used for 10 years until your child weighs 120 pounds.

Diono is a leading manufacturer of car seats and creates some of the best for children of all ages. Diono seats may include, but aren’t limited to: 

  • Full steel frame
  • Reinforced sides
  • Energy absorbing EPS foam 
  • Side impact protection
  • Safe Stop energy absorbing harness
  • Heavy


Diono car seats are so innovative and safe that they’ve gained many awards. They have won awards such as:

  • Most Innovative Product Award
  • Best Junior Car Seat
  • Top Choice of the Year
  • PTPA Seal of Approval
  • Best Buy Award
  • Silver Award

So the question here is whether or not Diono car seats are worth it. On paper it seems like these car seats would seem like the best, but in reality, they aren’t. We don’t believe that these car seats are worth the price.

Sure, the company won a bunch of awards and the seats seem to have innovative technology, but when looking at reviews, it seems like the seats are too difficult to install, heavy, and they are very expensive. Not to mention, they aren’t non-toxic.  

Are Diono Car Seats Safe?

Diono car seats are among the safest in the industry since they are made with a steel frame and EPS energy-absorbing foam.

These two features alone make the car seat safer than any car seat with a plastic shell. There’s no doubt that this brand creates some of the safest car seats on the market. 

In addition to some of the safety features, Diono also creates car seats that are designed to allow your child to remain in a rear-facing position for longer, which is the safest position they can be in. 

Are Diono Car Seats FAA Approved?

FAA-approved car seats are recommended for children weighing up to 40 lbs. The car seat must have a certified harness system. It’s important to note that airline rules may vary, so if you’ve used a car seat on one airline, you can’t assume that you can use it on another airline.

There are also car seat rules that you must follow when traveling with your Diono car seat. You can’t use it in an emergency exit row and they can only be used in a window seat so it doesn’t block the escape path in the event of an emergency. 

Not all Diono car seats are FAA-approved but here is a list of the ones that are: 

  • Rainier
  • Olympia
  • Radian RXT
  • Radian 3R Series
  • Radian 3Q Series
  • All convertible seats

Where Are Diono Car Seats Made?

It’s unfortunate that even though Diono is in Seattle, Washington, their car seats are made in China. Many individuals prefer their car seats to be manufactured in the USA, but this is not the case. 

How Long Does A Diono Car Seat Last?

Most Diono car seats have an expiration of 6-10 years. However, the expiration of a Diono car seat depends on the model. Here’s a breakdown of each car seat and its expiration: 

  • Radian Models – 10 Years
  • Ranier, Pacifica, Olympia – 8-10 Years
  • Monterey – 8 Years
  • Monterey XT, Cambria, Hip, Solana – 6 Years
  • Everett Models – 8-10 Years

Where Is The Expiry Date on A Diono Car Seat?

You can find the expiry date on the manufacturer label at the bottom, back, or side of the car seat.

It will be somewhere near the manufacturer’s warning stickers. On this sticker, you will find the model, manufacturer location, when it was made, and the serial number for that particular car seat. 

Here are the locations of the expiration date on each car seat: 

  • Radian 3QXT – Side
  • Radian 3Qx – Back
  • Radian 3RX Luxe 2020 – SIde
  • Radian 3EXT – Back
  • Radian 3RX – Back
  • Radian 3R – Back
  • Monterey 4DXT – Bottom
  • Monterey XT – Bottom
  • Everett NXT – Bottom
  • Cambria 2 – Bottom
  • Solana 2 – Bottom

What To Do With An Expired Car Seat

If you have just discovered that your car seat has expired, you can simply hold on to it and wait for a trade-in program that becomes available occasionally at retail stores.

If you bring it to them, they will give you credit towards a new car seat or store credit on something else. If you decide to throw the car seat away, make sure you destroy the straps so nobody else can use it.

Best Diono Car Seat For 1-Year-Old

The Diono Radian 3QX 4-in-1 car seat is our choice for the best seat for a 1-year-old. We chose this one because even though it seems clunky and strange, it’s safe and comfy. It can be used for 10-years and accommodate children up to 120-pounds.

It’s the only car seat you’ll need. It doesn’t come with an infant insert, but it does come with a travel wedge, harness pad, and positioning liner. 

One of our favorite things about this car seat is that it folds up flat for traveling and it can easily fit three across.

It’s important that a car seat is not only safe but convenient. The main difference between this model and the 3QXT is that this model only has 6 layers of side impact protection as opposed to 8 and it doesn’t have a side impact management pod. 

Lightest Diono Car Seat

The lightest Diono car seat is actually the Everett NXT Booster. It was one of the lightest in its class.

We appreciate the fact that there are 7 positions on the headrest and a handle that allows for easy adjustment. There’s also an abundance of padding on each side for optimal head protection in the event of an accident. 

You can install the booster multiple ways and each is generally very easy to understand. It won’t cause a headache when trying to transport between vehicles either.

Additionally, the fabric is machine washable, so if you have a messy child, you’ll love this feature. The only issue we found was that there was a slight rattle from the seat while driving. No big deal though.

Best Diono Car Seat for A 5-Year-Old

We can say with a fair amount of certainty that the Diono Radian Monterey 4DXT is the best car seat for a 5-year-old. It’s an expandable booster that has breathable side panels that keeps your child cool and comfortable on even the longest rides.

Our favorite feature of this booster is the hideaway cup holders. They can be tucked away until your child wants to use them. 

Additionally, a handy feature is the width adjustment. If your child is a little larger than others in that age group, you can adjust the seat to fit them better.

Lastly, it can be converted into a backless booster and there are seven colors to choose from. The only issue is that you can machine wash the fabric, but it has to be line dried. 

Best Diono Car Seat 3 Across

We chose the Diono Radian 3R as the best for fitting 3 across because it’s actually the original 3 across car seat. They are so slim, they can be lined up next to one another in the back seat easily and comfortably. This is the perfect solution for parents with multiple children in the same age group. 

It’s great that the car seat offers extended rear-facing and front-facing security. The frame is constructed from heavy-duty integrated steel and the seat is made with comfortable memory foam.

You can use the car seat from infancy all the way to the booster stage and 100 pounds.  The installation was fairly simple thanks to the SuperLatch audible-click and visual-locking indicators. 

Best Infant Diono Car Seat

We can say with a fair amount of certainty that the Diono Radian 3QXT is the best car seat for an infant. It can accommodate a child from 4-120 pounds and has a lifespan of 10-years. So it’s the only car seat you’ll ever need. We were impressed with the easy-click installation. It was one of the easiest to install by far. Additionally, the slim profile will allow for multiple seats to be installed side-by-side. 

There are 12 headrest positions that grow with your child and a four-stage newborn protection package. You’ll get a neck insert, travel wedge, harness pads, and positioning liner.

The travel wedge helps properly angle your baby to open airways for easier breathing. Lastly, if your child has a blowout of another type of mishap, you can easily remove the fabric and throw it in the washing machine. 

Final Thoughts

We hope that you were able to gain some handy knowledge regarding the Diono brand. As we’ve mentioned, they aren’t the cheapest brand, but their car seats are generally quite safe. However, safety alone doesn’t make them worth the price.

All of their seats are either convertible or boosters, so purchasing a plain infant seat is out of the question. This could cause an issue when it comes to switching seats between vehicles. 

Other than the frustration with installation and lack of infant seats, Diono is a decent brand. It’s upsetting that they don’t make their car seats in the USA, though. 

Avatar of Keren Simanova

Welcome to my car seat blog! As a mom of 3, I put together with other hard-working moms a highly informative one-stop car seat resource, full with many reviews and buyer guides. I hope you find it invaluable. Thank you for trusting me & my team! - Keren

Write A Comment